Fix test error "fatal: empty ident name (for <(null)>) not allowed"

Occurs when tests run with tox not with Travis CI or Appveyor

Changed existing tox setenv statement to use whitespace around `=` as per
http://tox.readthedocs.io/en/latest/example/basic.html#setting-environment-variables

.travis.yml

@@ -8,10 +8,7 @@ env: # These should match the tox env list
     - TOXENV=py27 LATEST_GIT=1
 install: pip install coveralls tox
 script: tox
-# Special snowflake.  Our tests depend on making real commits.
 before_install:
-    - git config --global user.name "Travis CI"
-    - git config --global user.email "user@example.com"
     # Our tests inspect some of *our* git history
     - git fetch --unshallow
     - git --version